The direct decomposition of NO over the la2CuO4 nanofiber catalyst

Abstract

The NO catalytic direct decomposition was studied over La 2CuO4 nanofibers, which were synthesized by using single walled carbon nanotubes (CNTs) as templates under hydrothermal condition. The composition and BET specific surface area of the La2CuO4 nanofiber were La2Cu0.88 2+Cu 0.12 +O3.94 and 105.0m2/g, respectively. 100% NO conversion (turnover frequency-(TOF): 0.17 g NO/gcatalystS) was obtained over such nanofiber catalyst at temperatures above 300°C with the products being only N2 and O2. In 60 h on stream testing, either at 300°C or at 800°C, the nanofiber catalyst still showed high NO conversion efficiency (at 300°C, 98%, TOF: 0.17 gNO/gcatalysts; at 800°C, 96%, TOF: 0.16 gNO/gcatalystS). The O2 and NO temperature programmed desorption (TPD) results indicated that the desorption of oxygen over the nanofibers occurred at 80-190 and 720-900°C; while NO desorption happened at temperatures of 210-330°C. NO and O2 did not competitively adsorb on the nanofiber catalyst. For outstanding the advantage of the nanostate catalyst, the usual La2CuO4 bulk powder was also prepared and studied for comparison. © 2008 Elsevier Inc. All rights reserved.